In operation, internal combustion engines discharge heat energy into the external environment through exhaust gas, engine cooling systems, charge air cooling systems, etc. The discharged heat energy that is not used to perform useful work is typically known as “waste heat.” WHR systems capture a portion of the waste heat to perform useful work. Some WHR systems utilize a Rankine cycle (“RC”). The RC is a thermodynamic process in which heat is transferred to a working fluid in an RC circuit. The working fluid is pumped to a heat exchanger where it is vaporized. The vapor is passed through an expander and then through a condenser, where the vapor is condensed back to a fluid. The expanding working fluid vapor causes the expander to rotate, thereby converting the waste heat energy to mechanical energy. The mechanical energy may be transmitted to engine system components, such as a pump, a compressor, a generator, etc.